OBD Guide

P257B

Vacuum Reservoir Control Circuit Low

P257B is an OBD-II diagnostic trouble code meaning: Vacuum Reservoir Control Circuit Low. Common causes: open or short circuit in control circuit, vacuum reservoir sensor malfunction. Estimated repair cost: $17–56.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$17–56 (est.)

Symptoms

  • Check Engine Light Is On
  • Deterioration of the brake system
  • Uneven engine operation
  • Reduced engine power
  • Problems with the EGR system

Causes

  • Open or short circuit in control circuit
  • Vacuum reservoir sensor malfunction
  • Solenoid valve problems
  • Vacuum reservoir malfunction
  • Wiring harness damage

How to Fix

  1. Check the integrity of the control circuit
  2. Test the vacuum reservoir sensor
  3. Check the operation of the solenoid valve
  4. Inspect and, if necessary, replace the vacuum reservoir
  5. Check the condition of the wiring harness

Related codes

Error P257B by Vehicle Brand

FAQ

What does the P257B code mean?

P257B is an OBD-II diagnostic trouble code that indicates: Vacuum Reservoir Control Circuit Low

What causes a P257B error code?

The most common causes of P257B include: Open or short circuit in control circuit; Vacuum reservoir sensor malfunction; Solenoid valve problems; Vacuum reservoir malfunction.

How do I fix a P257B diagnostic trouble code?

To fix P257B: Check the integrity of the control circuit. Test the vacuum reservoir sensor. Check the operation of the solenoid valve. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P257B?

Limited driving only, diagnose soon

How much does it cost to fix P257B?

The estimated repair cost for P257B is $17–56. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat